Field
The present invention relates to the field of remote sensing of objects using LADAR and the application of LADAR to vehicular collision avoidance.
Related Art
Many collision avoidance systems have been built which rely on microwave radars, scanning LADARs, and passive thermal and IR sensing. LADAR systems typically require the transmission of a high energy illuminating pulse. Historically, these systems rely on solid state lasers operating in the near infrared with a lasing media of Neodymium-YAG or Erbium doped glass. Many of these systems utilize multiple pulses over a period of time to detect remote objects and improve range accuracy. These systems are often based on a single detector optical receiver. To develop a complete picture of a scene, the laser and optical receiver must be scanned over the field of view, resulting in a shifting positional relationship between objects in motion within the scene. Flash ladar systems overcome this performance shortcoming by detecting the range to all objects in the scene simultaneously upon the event of the flash of the illuminating laser pulse.
U.S. Pat. No. 4,403,220 awarded to Donovan describes a collision avoidance system based on a scanning microwave radar. U.S. Pat. No. 5,529,138 issued to Shaw and Shaw details a vehicle collision avoidance system based on a scanning LADAR or sets of scanning LADARs. U.S. Pat. No. 7,061,372 awarded to Gunderson, et. al. describes a modular collision avoidance sensor which may incorporate any number of sensor technologies, including LADAR, ultrasound, radar, and video or passive infrared sensing.
The present invention is a collision avoidance system enabled by a plurality of vehicle mounted flash ladar sensors incorporating elements of the flash ladar technology disclosed in Stettner et al, U.S. Pat. Nos. 5,696,577, 6,133,989, 5,629,524, 6,414,746B1, 6,362,482, and U.S. patent application US 2002/0117340 A1, and which provides with a single pulse of light the range to every light reflecting pixel in the field of view of the flash ladar sensor as well as the intensity of the reflected light.